title: Elution-extrusion counter-current chromatography separation of two new benzyl ester glucosides and three other high-polarity compounds from the tubers of Pleione bulbocodioides.
abstract: BACKGROUND
  The tubers of Pleione bulbocodioides (Franch.) Rolfe, with gastrodin and benzyl ester glucosides as main components, have been used in traditional Chinese medicine for the treatment of various cancers and bacterial infections. Up to now, their official quality control method is still inadequate, and the difficulty of obtaining these high-polarity compounds is one of the major reasons.
  
  
  OBJECTIVE
  To develop a rapid and efficient method for preparative separation of the high-polarity compounds gastrodin and benzyl ester glucosides.
  
  
  METHODS
  An optimised solvent system composed of n-butanol:ethanol:water (20:1:20, v/v/v) was applied for the elution-extrusion counter-current chromatography (EECCC) separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase at a flow rate of 1.5 mL/min, a rotation speed of 850 rpm and a temperature of 35°C.
  
  
  RESULTS
  Five high-polarity glucosides, including two new compounds, (E)-4-β-D-glucopyranosyloxycinnamic acid 9-(4-β-D-glucopyranosyloxybenzyl) ester (4 mg) and (Z)-2-(2-methylpropyl)butenedioic acid bis(4-β-D-glucopyranosyloxybenzyl) ester (9 mg), and three main components, gastrodin (87 mg), dactylorhin A (60 mg) and militarine (15 mg), with HPLC purities of 95.4%, 96.4%, 91.1%, 97.2% and 95.5% respectively, were yielded from 400 mg of the prepared sample.
  
  
  CONCLUSIONS
  Elution-extrusion counter-current chromatography could be used as a useful tool for the separation of high-polarity compounds such as gastrodin and benzyl ester glucosides and the enrichment of the minor ones.
authors.affiliation: School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, 110016, China; Shanghai Research Center for Modernization of Traditional Chinese Medicine, National Engineering Laboratory for TCM Standardization Technology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.forename: Shu-hong
authors.initials: SH
authors.lastname: Guan
authors.forename: Rui-hong
authors.initials: RH
authors.lastname: Feng
authors.forename: Jing-xian
authors.initials: JX
authors.lastname: Zhang
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Xiao-hui
authors.initials: XH
authors.lastname: Chen
authors.forename: Kai-shun
authors.initials: KS
authors.lastname: Bi
authors.forename: De-an
authors.initials: DA
authors.lastname: Guo
mesh_terms: D001592:Benzyl Alcohols / Q000302:isolation & purification*; D003377:Countercurrent Distribution / Q000379:methods*; D005960:Glucosides / Q000302:isolation & purification*; D019906:Nuclear Magnetic Resonance, Biomolecular; D029595:Orchidaceae / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D035281:Plant Tubers / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D001592:Benzyl Alcohols; D005960:Glucosides; D010936:Plant Extracts; C045345:gastrodin
keywords: Counter-current chromatography; Pleione bulbocodioides; benzyl ester glucosides; gastrodin; high-polarity